You see opinions are funny things. Sometimes opinions are valid and sometimes not. An opinion about whether a game/TV show/Movie is good is always valid, because it comes down to subjective personal taste. And if you like a movie everyone hates that does not make your opinion invalid, because it is personal to you. And liking something is a purely subjective thing that does not need to be supported by data and objective evidence. Similarly if you hate a game everyone likes. Personal taste.

However an opinion about some future event that has a definitive binary outcome (Xb one will either win or lose BF vs PS4) is not purely subjective and there is a lot of objective information available to help formulate a valid opinion, or information to ignore to help formulate an invalid (or less valid if we are going to be kind) opinion. The validity of an opinion can be questioned and criticised based on whether current evidence tends to support said opinion being more or less likely to turn out to be correct. On current evidence it seems your opinion is unlikely to be correct, though not impossible, so you should not be surprised to see people criticise your opinion especially when you convey it in the way you have in some of your posts, which lack any rational evidence as a basis for your opinion. So sure, If Xbox fans do turn up in a thread and make speculative comments about future sales which are not supported by evidence then expect their opinions to be criticised as lacking validity. If I say my opinion is that Xb one will eventually win in Europe, it doesn't suddenly become immune to criticism, because, hey, it's my opinion man. My opinion is not valid based on current sales evidence and therefore the likelihood of my opinion being true is extremly low.

Fact of the matter is, you're making a prediction about BF, you're not voicing an opinion. Unbiased predictions should be based on all relevant evidence that is currently available, free from personal preference. Is your prediction really based on all currently available evidence and free from personal preference? I would say it is not, in fact it is a prediction which is being made contrary to current evidence. Hence it appears what you are doing is making a biased prediction based on what you want the outcome to be, not what the outcome is likely to be. Should predictions based on preference rather than evidence be immune to criticism? I don't think so. And indeed when it seems like a prediction is being made based on preference and contrary to evidence it is fair to question the motives of the person making such a prediction.

If we get some new evidence, like The Halo 5 LE bundle being dropped to $350, then that can have a material effect on the likely outcome and it requires everyone to reviswe their predictions about the most likely outcome for BF. But so far it seems the deals we know about are favouring PS4.

If you wish to advance the view that Xb one at #10 and #15 on Amazon probably beats PS4 at #1 and #19 (all skus outside the top 20 being negligible, for argument's sake), then you can certainly try to construct an argument to this effect, which may or may not be very convincing. If you can't construct a rational argument for why Xb one will win BF / November then perhaps you should stop making the prediction until you do have some evidence.

Without a significant pre-order effect in play, Amazon has been totally reliable at predicting the NPD winner. What have you got for us that strongly contradicts that very reliable pattern? At the moment the monthlies have 4 PS4 skus above the highest Xb one sku. So far November looks to be more in PS4's pocket than any other month since these consoles launched.